Transcript for Malaysian Airlines Flight 370: Did Cockpit Actions Show Disappearance Was No Accident?

Breaking news in the mystery of the passenger plane that vanished into thin air. US investigators tell ABC news they are considering the possibility based on new clues. That what went on inside the cockpit of this plane may not have been an accident. All of this as a US ship -- to a new location in the Indian Ocean and ABC's David -- brings us the breaking details right now David. Good evening -- tonight two sources tell ABC news that two communication systems on this triple seven were shut down. Separately. Suggesting there was not a catastrophic failure these communications systems shut down separately as I said that less than an hour and a flight. Our source called it systematic. This as the search is expanded. American ships are on the move tonight looking for that triple seven jetliner even farther away from its original flight -- A top US military source says there's an indication the jet went down in the Indian Ocean so the search grid is getting bigger and could get much bigger. Here's why to senior US officials tell ABC news the plane may have flown up to -- four hours be on its last sighting on radar. They know this because the jet was apparently pinging a satellite every hour it's part of a monitoring system airlines can pay -- to keep track of the jets in the air. Malaysia airlines was not -- but our sources say even if the airline isn't buying the data the jets still sends a signal to the satellite. Based on some new information that's not necessarily conclusive but new information. An additional search area may be open in the Indian Ocean. Flying for hours at 600 miles an hour means Malaysian flight 370 could have traveled 2400. Miles. But it's unclear which way those satellite -- don't give direction and would not be able to transmit from the bottom of the ocean. I don't think that the aircraft is underwater that she'll get a valid signal coming up from that the bottom of the sea. This latest information comes from US sources days after conflicting stories in -- -- remember those satellite photos from China which showed floating debris. The Malaysians look today found nothing and say they were told by the Chinese that these images were released by mistake. With our sources telling us these communications systems were shut down intentionally. -- suggests either -- hijacking or pilot suicide. But now this search area shifting here to the massive Indian Ocean. As I showed you in the graphic 2400. Square miles -- -- a grid over it it is going to take months to search -- all right thank you David.

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